Choke fitting



Jec. 28, 1948.

C. W. MALIPH'ANT CHOKE FITTING Filed May 31; 1944 INVENTOR. CHARLES W MAL/PHANT ATTORNEY Patented Dec. 28, 1948 GHOK-E nr'rme.

iQhar esrW- Me irbena e d ea .essi n to The westm'ghopse Brake Company, Wilme siine, liezalcqr h f Reen r venia. Application'lvlay 31, 1944, SerialNp. 538,178

1- an eventiee relate io fluid treamer-1 94- struotion of thetyp to be.used i a fluid disa rees? el a as new" whi ened.

l eh h lrasse,. reaches the choked port in the plug.

A further object.- of the. invention is to provide an im lQreq..- 9 .P ae 2f, the share t r in which a fibrous fluid straining means isernplgyed that has a large surface area exposed to fluid to be cleansed in" order to preventfclogging of the fluid straining means and resultant restriction of the new of'fluid therethrou'gh to the choked port the plug collected foreign matter separated from the fluid,

Another object is to provide anir-nproved choke plug of the type described in the pr eceding paragraph having means whereby the fibrous fluid cleansing material is so supp rted that it willbe.

main ain d n s ssiaway he, the s e par a su flicient distance that it will not restrict the flow of fluid through the port in the choke plug.

A further object is to provide a choke plug having simple but very efiective means for mounting and 'removably securing the straining element therein.

Other objects of the invention and features of novelty will be apparent from the following description taken in connection with the accompanying drawing, in which Fig. 1 is a fragmentary sectional view of an improved brake controlling valve device embodying the invention, and Fig. 2 is a detail cross-sectional view taken on the line 2-2 of Fig. 1.

Referring to the drawing, there is illustrated therein a fragment of the emergency portion of a. brake controlling valve device of the type shown and described in U, S. Patent No. 2,031,213, issued February 18, 1936, to C. C. Farmer. The emergency portion comprises a body I having a, bore therein in which is positioned a bushing 2 which has mounted therein a piston 3 having at one face a chamber 4 which is constantly connected to brake pipe, not shown, by means of a communication having an air strainer, not shown, interposed therein. Piston 3 has at its other face a valve chamber 5 which is constantly connected to a quick action chamber formed in a pipe bracket section, not shown.

The piston 3 is reciprocable in the bushing 2 and atone point its range of movement opens.

wmmunisaiio iir niih ham 5w wort in a. bush-in 2 hi h emmuni e es hef as a or conductor 1 in the body I through which fluid 0 e alve elr mbe 5. and'to the quick a t chamber.

Thepassage I in the body I has a choke plug di a d yhe re e e ee um ra u e he e n t etrq h ew 9 fl id romm br ev o the alv hambe 5 an t h w sh.

sfinnehembere, h9 .1; in't a drawin haise us? 9 1 rise a ear 9 w ell ma h med of meni le. mater al ur v as r ss- Fo mal-71 h earti' r' h eer i rqv d dwi h tap ed;

threads; I 2 for engaging corresponding threads [3. formed the wall ofthe. passage 1. T helower end of the body terminates in a cylindrical porp i of i h ly smal e di mete than t est-l m it-t read d edit on,- r

Lesaiadin th ird p alr ri n .4. a enia relation to the body 9 is a bore [5 which is Op the recess H] by way of an axial restricted port or passage l6. For a short distance one end of this bore tapers inwardly to the adjacent open end of the passage l6 and where the surface of this end of the bore merges into the surface of that portion of the bore which has the greatest diameter, the tapering surface serves as an annular led e or slot for a member which Will be described later herein. At the other end of this bore the portion 1 4 of the body 9 is provided with an inwardly extending relatively thin narrow annular flange l8 having an inner diameter slightly smaller than that of the bore.

Associated with the body 9 is a fluid straining element l9 which may be formed of any suitable material, but preferably of a compacted fibrous material such as felt, in a cylindrical body of slightly larger diameter than that of the bore l5. Thi felt body may be inserted in the bore 15 of the cylindrical portion [4, and being of slightly larger diameter than the bore, will be compressed somewhat when inserted therein so that it is held in firm engagement with the surface of the bore and with the inner periphery of the flange I8 by the inherent resiliency of the material of which it is constructed. Interposed between .the straining element l9 and the conical surface H of the bore I5 is a retaining or seat member 20 which may consist of a metallic wire formed in the general shape of a letter S. Thi member 20 serves as a retainer .or stop to prevent the strainer element I!) from engaging the conical surface 11; thus at all times insuring the maintain-ance of an unoccupied chamber between the air straining element and the adjacent open end of the re-j stricted passage I6. From this it will be obvious that the straining element cannot be accidentally forced into the tapering portion of the bore l thereby effectively eliminating any possibility of the clogging of the choke passage I 6 by the.

element. I

It is intended that the air strainingelement I9 relation to the passage '1 in which it is mounted I that the straining element will be spaced away from the walls of the passage so that there will always be a clear space exteriorly of the exposed portion of the element.

In the service for which this invention is intended, the flow of fluid to the passage in which the strainer is mounted is normally in one direction only, and therefore, as shown in the drawing the strainer is arranged so that when fluid flows through the port 6 in the bushing 2 to the passage 4 1, it will then flow through the air straining ele ment [9 before reaching restricted passage l6 which is to be protected. If the fluid supplied to the passage 1 contains any foreign matter, it will be removed by the straining element l9 before reaching the restricted passage It in the choke plug 8 where it might partially or completely close the passage, thereby interfering with the intended operation of the valve device. Thus the flow of fluid to the choke plug is'through the straining element l9 into the body 9 of thechoke plug, and therefore there will be no tendency of For instance, a

4 dislodgement of this element by this flow of fluid, the tendency of such flow being to seat the element more firmly on the seat member 29.

It should here be noted that if that end portion of the straining element which is contained in the bore l5 could be forced into the tapered portion of the here it would tendto restrict the flow of fluid through the element. Since, however,-the seat member prevents the element from engaging the tapering surface I! the end of the element maintains its large flow area and thus insures the free flow of fluid from the element to the port 18.

Having now described my invention, what I claim as new and desire to secure by Letters Patent; is: I

A removable choke plug comprising a body having a fluid flow'restricting bore open to one end of said body, an axial bore of larger diameter connecting'said restricting bore to the opposite end of said body to permit flow of fluid in the direction from said larger bore to said restricting bore, said body comprising at the outer end of said larg er bore an inwardly directed annular flange, and a removable compressible filter elementcomprising a portion disposed in said larger bore, a portion disposed outside said body beyond said opposite end, and an intermediate portion disposed withinand compressed by said annular flange'for removably holding, said filter element in said body.

CHARLES W. MALIPHANT;

REFERENCES CITED The following references are of recordin the.

file of this patent:

UNITED STATES PATENTS Number Name v 439,091 Bach Oct. 28, 1890 1,496,947 Robinson June 10, 1924 1,862,482 Kocher June 7, 1932 1,994,460 Bijur Mar. 19, 1935 FOREIGN PATENTS Number Country Date 79,774 Germany Apr. 10, 1894 Date 

